Open sign



FIG. 1 is an isometric view of a first embodiment of an open sign incorporating my new design, wherein the portions shown in phantom form no part of the claimed design;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is a first side elevation view thereof;

FIG. 5 is a second side elevation view thereof;

FIG. 6 is a top plan view thereof; and,

FIG. 7 is a bottom plan view thereof.

The broken lines illustrate portions of the open sign that form no part of the claimed design. 

CLAIM The ornamental design for an open sign, as shown and described. 